A product that has recently gained popularity with campers, hikers and people involved in other outdoor activities is a portable stove that can be used to quickly and efficiently heat a liquid/food item in a containing vessel. One such stove and vessel is described in co-pending U.S. patent application Ser. No. 10/603,947, assigned to the assignee of the present invention.
As described in that patent application, in order to insulate the vessel from the loss of heat to the atmosphere, and in order to allow the user to freely handle the vessel without touching a hot surface, an insulative cover is provided around the outer side of the vessel. However, either with or without the insulative cover, it is generally been necessary for the user to look inside of the vessel in order to determine whether the contained material has reached the desired temperature. That is, for coffee, for example, it is desired that the temperature of the water within the vessel reaches the boiling point of 100° centigrade. If the user needs to open the lid to view the liquid to determine its temperature, heat will be lost to the atmosphere, each time that this occurs. Further, for desired temperatures below the boiling level, it is difficult to determine by this method, the temperature of the liquid inside the vessel.
What is needed is a method/apparatus for indicating to the user, in a simple and effective manner, when the temperature of the material inside the vessel has reached a predetermined temperature level.